1 /*
2  * Copyright (C) 2011-2013 Michael Niedermayer (michaelni@gmx.at)
3  *
4  * This file is part of libswresample
5  *
6  * libswresample is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * libswresample is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with libswresample; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #ifndef SWR_INTERNAL_H
22 #define SWR_INTERNAL_H
23 
24 #include "swresample.h"
25 #include "libavutil/channel_layout.h"
26 
27 #include "config.h"
28 
29 #define SWR_CH_MAX 32
30 
31 #define SQRT3_2      1.22474487139158904909  /* sqrt(3/2) */
32 
33 #define NS_TAPS 20
34 
35 #if ARCH_X86_64
36 typedef int64_t integer;
37 #else
38 typedef int integer;
39 #endif
40 
41 typedef void (mix_1_1_func_type)(void *out, const void *in, void *coeffp, integer index, integer len);
42 typedef void (mix_2_1_func_type)(void *out, const void *in1, const void *in2, void *coeffp, integer index1, integer index2, integer len);
43 
44 typedef void (mix_any_func_type)(uint8_t **out, const uint8_t **in1, void *coeffp, integer len);
45 
46 typedef struct AudioData{
47     uint8_t *ch[SWR_CH_MAX];    ///< samples buffer per channel
48     uint8_t *data;              ///< samples buffer
49     int ch_count;               ///< number of channels
50     int bps;                    ///< bytes per sample
51     int count;                  ///< number of samples
52     int planar;                 ///< 1 if planar audio, 0 otherwise
53     enum AVSampleFormat fmt;    ///< sample format
54 } AudioData;
55 
56 struct DitherContext {
57     enum SwrDitherType method;
58     int noise_pos;
59     float scale;
60     float noise_scale;                              ///< Noise scale
61     int ns_taps;                                    ///< Noise shaping dither taps
62     float ns_scale;                                 ///< Noise shaping dither scale
63     float ns_scale_1;                               ///< Noise shaping dither scale^-1
64     int ns_pos;                                     ///< Noise shaping dither position
65     float ns_coeffs[NS_TAPS];                       ///< Noise shaping filter coefficients
66     float ns_errors[SWR_CH_MAX][2*NS_TAPS];
67     AudioData noise;                                ///< noise used for dithering
68     AudioData temp;                                 ///< temporary storage when writing into the input buffer isn't possible
69     int output_sample_bits;                         ///< the number of used output bits, needed to scale dither correctly
70 };
71 
72 struct SwrContext {
73     const AVClass *av_class;                        ///< AVClass used for AVOption and av_log()
74     int log_level_offset;                           ///< logging level offset
75     void *log_ctx;                                  ///< parent logging context
76     enum AVSampleFormat  in_sample_fmt;             ///< input sample format
77     enum AVSampleFormat int_sample_fmt;             ///< internal sample format (AV_SAMPLE_FMT_FLTP or AV_SAMPLE_FMT_S16P)
78     enum AVSampleFormat out_sample_fmt;             ///< output sample format
79     int64_t  in_ch_layout;                          ///< input channel layout
80     int64_t out_ch_layout;                          ///< output channel layout
81     int      in_sample_rate;                        ///< input sample rate
82     int     out_sample_rate;                        ///< output sample rate
83     int flags;                                      ///< miscellaneous flags such as SWR_FLAG_RESAMPLE
84     float slev;                                     ///< surround mixing level
85     float clev;                                     ///< center mixing level
86     float lfe_mix_level;                            ///< LFE mixing level
87     float rematrix_volume;                          ///< rematrixing volume coefficient
88     float rematrix_maxval;                          ///< maximum value for rematrixing output
89     enum AVMatrixEncoding matrix_encoding;          /**< matrixed stereo encoding */
90     const int *channel_map;                         ///< channel index (or -1 if muted channel) map
91     int used_ch_count;                              ///< number of used input channels (mapped channel count if channel_map, otherwise in.ch_count)
92     enum SwrEngine engine;
93 
94     struct DitherContext dither;
95 
96     int filter_size;                                /**< length of each FIR filter in the resampling filterbank relative to the cutoff frequency */
97     int phase_shift;                                /**< log2 of the number of entries in the resampling polyphase filterbank */
98     int linear_interp;                              /**< if 1 then the resampling FIR filter will be linearly interpolated */
99     double cutoff;                                  /**< resampling cutoff frequency (swr: 6dB point; soxr: 0dB point). 1.0 corresponds to half the output sample rate */
100     enum SwrFilterType filter_type;                 /**< swr resampling filter type */
101     int kaiser_beta;                                /**< swr beta value for Kaiser window (only applicable if filter_type == AV_FILTER_TYPE_KAISER) */
102     double precision;                               /**< soxr resampling precision (in bits) */
103     int cheby;                                      /**< soxr: if 1 then passband rolloff will be none (Chebyshev) & irrational ratio approximation precision will be higher */
104 
105     float min_compensation;                         ///< swr minimum below which no compensation will happen
106     float min_hard_compensation;                    ///< swr minimum below which no silence inject / sample drop will happen
107     float soft_compensation_duration;               ///< swr duration over which soft compensation is applied
108     float max_soft_compensation;                    ///< swr maximum soft compensation in seconds over soft_compensation_duration
109     float async;                                    ///< swr simple 1 parameter async, similar to ffmpegs -async
110     int64_t firstpts_in_samples;                    ///< swr first pts in samples
111 
112     int resample_first;                             ///< 1 if resampling must come first, 0 if rematrixing
113     int rematrix;                                   ///< flag to indicate if rematrixing is needed (basically if input and output layouts mismatch)
114     int rematrix_custom;                            ///< flag to indicate that a custom matrix has been defined
115 
116     AudioData in;                                   ///< input audio data
117     AudioData postin;                               ///< post-input audio data: used for rematrix/resample
118     AudioData midbuf;                               ///< intermediate audio data (postin/preout)
119     AudioData preout;                               ///< pre-output audio data: used for rematrix/resample
120     AudioData out;                                  ///< converted output audio data
121     AudioData in_buffer;                            ///< cached audio data (convert and resample purpose)
122     AudioData silence;                              ///< temporary with silence
123     AudioData drop_temp;                            ///< temporary used to discard output
124     int in_buffer_index;                            ///< cached buffer position
125     int in_buffer_count;                            ///< cached buffer length
126     int resample_in_constraint;                     ///< 1 if the input end was reach before the output end, 0 otherwise
127     int flushed;                                    ///< 1 if data is to be flushed and no further input is expected
128     int64_t outpts;                                 ///< output PTS
129     int64_t firstpts;                               ///< first PTS
130     int drop_output;                                ///< number of output samples to drop
131 
132     struct AudioConvert *in_convert;                ///< input conversion context
133     struct AudioConvert *out_convert;               ///< output conversion context
134     struct AudioConvert *full_convert;              ///< full conversion context (single conversion for input and output)
135     struct ResampleContext *resample;               ///< resampling context
136     struct Resampler const *resampler;              ///< resampler virtual function table
137 
138     float matrix[SWR_CH_MAX][SWR_CH_MAX];           ///< floating point rematrixing coefficients
139     uint8_t *native_matrix;
140     uint8_t *native_one;
141     uint8_t *native_simd_one;
142     uint8_t *native_simd_matrix;
143     int32_t matrix32[SWR_CH_MAX][SWR_CH_MAX];       ///< 17.15 fixed point rematrixing coefficients
144     uint8_t matrix_ch[SWR_CH_MAX][SWR_CH_MAX+1];    ///< Lists of input channels per output channel that have non zero rematrixing coefficients
145     mix_1_1_func_type *mix_1_1_f;
146     mix_1_1_func_type *mix_1_1_simd;
147 
148     mix_2_1_func_type *mix_2_1_f;
149     mix_2_1_func_type *mix_2_1_simd;
150 
151     mix_any_func_type *mix_any_f;
152 
153     /* TODO: callbacks for ASM optimizations */
154 };
155 
156 typedef struct ResampleContext * (* resample_init_func)(struct ResampleContext *c, int out_rate, int in_rate, int filter_size, int phase_shift, int linear,
157                                     double cutoff, enum AVSampleFormat format, enum SwrFilterType filter_type, int kaiser_beta, double precision, int cheby);
158 typedef void    (* resample_free_func)(struct ResampleContext **c);
159 typedef int     (* multiple_resample_func)(struct ResampleContext *c, AudioData *dst, int dst_size, AudioData *src, int src_size, int *consumed);
160 typedef int     (* resample_flush_func)(struct SwrContext *c);
161 typedef int     (* set_compensation_func)(struct ResampleContext *c, int sample_delta, int compensation_distance);
162 typedef int64_t (* get_delay_func)(struct SwrContext *s, int64_t base);
163 typedef int     (* invert_initial_buffer_func)(struct ResampleContext *c, AudioData *dst, const AudioData *src, int src_size, int *dst_idx, int *dst_count);
164 
165 struct Resampler {
166   resample_init_func            init;
167   resample_free_func            free;
168   multiple_resample_func        multiple_resample;
169   resample_flush_func           flush;
170   set_compensation_func         set_compensation;
171   get_delay_func                get_delay;
172   invert_initial_buffer_func    invert_initial_buffer;
173 };
174 
175 extern struct Resampler const swri_resampler;
176 
177 int swri_realloc_audio(AudioData *a, int count);
178 
179 void swri_noise_shaping_int16 (SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count);
180 void swri_noise_shaping_int32 (SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count);
181 void swri_noise_shaping_float (SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count);
182 void swri_noise_shaping_double(SwrContext *s, AudioData *dsts, const AudioData *srcs, const AudioData *noises, int count);
183 
184 int swri_rematrix_init(SwrContext *s);
185 void swri_rematrix_free(SwrContext *s);
186 int swri_rematrix(SwrContext *s, AudioData *out, AudioData *in, int len, int mustcopy);
187 void swri_rematrix_init_x86(struct SwrContext *s);
188 
189 void swri_get_dither(SwrContext *s, void *dst, int len, unsigned seed, enum AVSampleFormat noise_fmt);
190 int swri_dither_init(SwrContext *s, enum AVSampleFormat out_fmt, enum AVSampleFormat in_fmt);
191 
192 void swri_audio_convert_init_aarch64(struct AudioConvert *ac,
193                                  enum AVSampleFormat out_fmt,
194                                  enum AVSampleFormat in_fmt,
195                                  int channels);
196 void swri_audio_convert_init_arm(struct AudioConvert *ac,
197                                  enum AVSampleFormat out_fmt,
198                                  enum AVSampleFormat in_fmt,
199                                  int channels);
200 void swri_audio_convert_init_x86(struct AudioConvert *ac,
201                                  enum AVSampleFormat out_fmt,
202                                  enum AVSampleFormat in_fmt,
203                                  int channels);
204 #endif
205